The invention deals with an equipment for calcination for precalcining of powdered materials before their burning in a sintering equipment, namely of cement raw material farina before its burning in a rotary kiln, composed from a calcinating chamber, which is provided with means for input of powdered material and input of fuel with a simultaneous input of burning air and which is interconnected with a mixing channel, which is arranged between the input chamber of rotary kiln and the last cyclone of cyclone heat exchanger which is arranged before the rotary kiln.
Recently the material at a lot of used equipment with calcinating chambers for calcination of powdered materials, for instance of cement raw material farina, led usually to the lower part of calcinating chamber. To this area also the hot gases from one or more heat sources are led, for instance for clinker cooler, or from the rotary kiln. The powdered material is by the influence of the entering gases kinetic energy dispersed to the volume of calcinating chamber, whereas the desired endothermic reactionsxe2x80x94as for instance the dissociation of calcium carbonatexe2x80x94of the powdered material components are running at mixing of powdered material with the added fuel and burning air, or at mixing with the entering hot exhaust gases, The mixture of gases and of powdered material eventually also of particles of unburned fuel then flows upwards the calcinating chamber and it is led with a tube to a channel located between the rotary kiln and the lower cyclone of on after the kiln connected heat exchanger. In this channel then the finishing of the phase of thermal process for powdered material preparation before its entering into the rotary kiln.
The disadvantage of such type of calcinating equipment is the relatively high pressure energy loss of entering gases, caused by the necessity of sometimes multifold lifting of powdered material, especially in case when in the calcinating chamber a greater amount of material is retained, as it would be necessary for the desired calcination level. At not perfect adjusting of operational parameters there it appears additionally a falling down of entering powdered material downwards and subsequently directly into the rotary kiln, without passing the thermal process in the calcinating chamber.
There are known construction versions of calcinating chambers at which the powdered material and also the hot burning air with the fuel are led into the upper part of calcinating chamber. The arising mixture is then flowing downwards and from the bottom part of calcinating chamber is then it is transported through the tube into the gas channel, which connects the rotary kiln, respectively its input chamber with the lower cyclone of the to the chamber antecedent system of cyclone heat exchanger. But the powdered material at this construction version has not an other possibility, as to fall in direction of the gravitation forces that means downwards. So the time of staying of powdered material in the calcinating chamber of this type is relatively short, what deteriorates the possibility of its thermal processing that means the level of calcination. The effort for intensive swirling of powdered material leads additionally to increase of the pressure loss of hot burning air, which is led into the calcinating chamber for instance from the following clinker cooler.
The mentioned disadvantages have as consequence the worsening of technological process effectiveness and the increasing of investment and operation costs for unit of production.
The above mentioned disadvantages of construction solutions are in a considerable extent decreased by the object of this invention, which is a calcinating equipment for precalcination of powdered materials before their burning in a sintering equipment, namely cement raw material farina before burning in rotary kiln, composed from a calcinating chamber provided with means for input of powdered material and input of fuel with simultaneous input of burning air and where it is connected with the mixing chamber, which is arranged between the input chamber of rotary kiln and the last cyclone of cyclone heat exchanger which is arranged before the rotary kiln.
The essence of the invention is that the calcinating chamber is connected to the mixing channel one the one hand with aid of the removing tube arranged in its lower part and on the other hand with at least one interconnecting tube, which is led out from its upper part, whereas the air tube for input of burning air is connected to the middlexe2x80x94working part of calcinating chamber, where this working part and/or the air tube are further provided with at least one input of powdered material and an input of fuel, whereas the working pail, the upper and lower part of calcinating chamber are advantageously coaxial.
An other essence of the invention is that the all parts of calcinating chamber have a circle cross-section, whereas the diameter of calcinating chamber upper part is lesser as the diameter of its working part.
The essence of the invention is also, that the mouth of removing tube is ended into the mixing channel closer to its lower part as the mouth of interconnecting tube.
An other essence of the invention is that into the air tube a regulating member is inserted eventually that into the air tube before its mouth into the calcinating chamber an auxiliary input of powdered material and an auxiliary fuel input are inserted.
At the and the essence of the invention is that the mixing channel is provided with additional input of powdered material, with additional fuel input and with an additional air input.
Using a construction according to the invention a better efficiency of calcinating equipment in whole is achieved and this at a lesser energy consumption. This is then manifested in decreasing investment and operation costs to unit of production.